Piston-packing.



E. DUGHESNE.

PISTON PACKING.

APPLICATION TILED APR.10, 1911v 1,008,799. Patented Nov. 14, 1911.

2 SHEETS-SHEET 1.

1 I W mg, 1

awuamtoz E. DUCHESNE.

PISTON PACKING.

APPLICATION FILED APR.10, 1911.

' Patented Nov. 14, 1911.

2 SHEETSSHEET 2'.

l w tumeo UNI STATES PATEN T. OFFICE.

ERNEST DUCHESNE, 0F VIAUVILLE, MQNTREAL, QUEBEC, CANADA.

PISTON-PACKING.

Specification of Letters Patent.

Patented Nov. 14, 1911.

Application filed April 10, 1911. Serial No. 620,052.

declare that the following is a full, clear,

and exact description of the same.

The invention relates to piston packing, as described in the presentspecification and illustrated in the accompanying drawings that formpart of the same. 7

The invention consists essentially in the novel arrangement andconstruction of rings in prepared grooves in the periphery of thepiston.

The objects of the invention are to devise a means of effectuallyavoiding leakage between the piston and the cylinder, to construct aself adjusting form of ring, and generally to provide a ringcomparatively cheap to manufacture and economical in regard tomaintenance.

In the drawings, perspective view of a portion of a piston,

showing the rings partly broken away. Fig.

2 is a perspective detail of the rings assembled, showing a part thereofpartly broken away. Fig. 3 are perspective details of the outer-ringsand the inner rings apart. Fig. 4 is aperspective detail of a portion ofthe piston,-showing the ring grooves. v Fig. 5 is a cross sectional viewof a portion of the piston, showing a means of fastening a ring at oneend thereof. Fig. 6 is a sectional detail, showing another means offastening a piston ring at one end. Fig. 7 is a cross sectional "iew ofthe rings assembled on the line AB in Fig. 2.

Like numerals of reference indicate corresponding parts in each figure.

Referring to the drawings, 1 is a piston having the grooves 2, saidgrooves each having the abutments or shoulders 3 and 4 forming'therebyin each groove a helical passage 5.

6 and 7 are piston rings of the split form having the overlapping andreduced ends 8 and 9, said rings extending from the abutments 3 and 4respectively, the inner wall of each ring 6 is beveled at 10, and theinner wall of each ring 7 is correspondingly beveled at 11 to formbetween the rlngs a V- shaped groove which terminates at said re- Figure1 is a sectional duced ends 8 and 9, said split rings 6 and 7 extendhelically around the piston in each groove 2.

12 is an inner ring, substantially V-shaped in cross section andextending into the V- shaped groove formed by the bevels 10 and 11 andon the inner side thereof abutting the bed of the groove 2, the sameform of inner ring being used in each of sa1d grooves 2.

13 is a pin inserted through a suitable plug 14, the latter beingarranged in a vcorresponding hole through the'wall of the piston fromthe inside, said pin 13 projecting into one of the grooves 2 and into acorresponding hole in the inner wall of the ring 6, adjacent to theabutment 3 and holding said ring firmly to said abutment. There is asimilar pin projecting into the ring 6, adjacent to the abutment 4 andholding said ring to said abutment, therefore, there is no space left inwhich any leak can occur between the cylinder wall and the piston, forthe overlapping ends 8 and 9 cannot separate to any extent, and if theydo separate slightly, the overlap prevents any leak. The samearrangement is made with the other pair of rings.

In Fig. 6, another means is shown for holding the ring ends to theabutments 3 and 4. 15 are springs rigidly secured to the bed of thegroove 2 toward each end thereof and engaging the rings 6 and 7 in theslots 16 and holding said ringsto said abutments 3 and 4. Other meansmay be employed for holding said rings to the abutments, but they arenot illustrated herein, as for instance, springs holding the other endsapart or separating the overlapping ends slightly, but it is hardlynecessary to -illustrate a number of forms, as some departures may bemade from the construction shown and described, so long as it is keptwithin the limits of thevclaims for novelty following thisspecification.

The inner ring 12 is of use in keeping the rings 6 and 7 to the sidewalls of the grooves 2 as any tendency to loosen from said side wallswill be overcome by the outward prescomprising a single helix withoverlapping ends, said rings being placed together in the groove to forma continuous helix, and means for retaining the outer extremities ofsaid continuous helix in rigid abutment With said shoulders.

"2. In piston packing, arpis ton having a groove in the peripherythereof terminating: at each end in abutments and a pair of split ringsmounted on saidpiston in said groove and abutting said abutments andreduced at their other ends and overlapping, and means for holding saidrings to said abutments. I

3. In piston packing, in combination a piston having a groove in itsperiphery .thereof terminating at each end in abutments and formingahelical passage around said piston, a pair 1 of split helical ringsmounted on said piston following the direction of said helical passageand abutting said abutments, an inner central helical ring substantiallyV-shaped in cross section and adapted to enter between the aforesaidrings for spreading the same, and means for holding said abutting endsto said abutments.

4:. In piston packing, a piston having a helical groove in the peripherythereof ter minating at each end in abutments, a pair of helical pistonrings abutting said abutments and following the direction of said grooveand meetingand overlapping in reduced ends, said rlngs having slots inthe inner wall thereof adjacent to said abutments, and springs rigidlysecured to said piston in the bed of said recess and engaging in saidslot and holding said abutting ends to said abutments.

Signed at the city and district of Montreal, Quebec, Canada, this sixthday of April, 1911. l

ERNEST DUOHESNE. Witnesses:

G. H. TRESIDDER, H. E. PLANTE, Jr.

